I do use Joplin a lot in my day to day basis on my cellphone and android tablet, thank you the community for providing this awesome application suite I have been using for years.
Especially on the tablet, I usually have it on the top of a table while I am working on something else, and I consult Joplin from time to time, but in other to prevent the screen from looking I have to use an external app.
I thought it would be a cool request for more users. Have a simple button that would prevent the screen from sleep. It would very nice for me.
interseting question! I never saw an app with a button for such a feature, so I wonder why you would not use the system settings of your tablet to prevent it going to sleep?
Some apps have a option in the setting which, when toggled, keeps the screen on. I think that could be what you wish, right?
I remember wanting Evernote to have this feature years ago so i could set my phone up and use it to keep a recipe displayed whilst cooking. Messing around with the system setting to do the same thing is a pain of you only want the feature for a short time every few days.
Like @Daeraxa statted its a few less steps, I think its such a simple feature that can save you some hassle.
Like on cases I am assembly a 3D printer or, doing some car project that you only go to Joplin for reference its such a time saver, plus having a button makes it easier not to forget to turn it off.